4130 question for you guys....

[Sberry]

Sounds better than a unit built in the backwoods with a buzz box, they went to the trouble of using expensive materials and are concerned with finish. I don't have ready access to powder coat but I got to agree with using paint finishes for the most part. Sand it up, epoxy primer and epoxy paint. I was trying to find some tubing pics but here is as near as it gets for the moment.
If I want it nice I sand then even sandblast all the grinding out sometimes, then scuff with Scotchbrite, blow the dust off and paint usually with Dupont Corlar epoxy primer followed by industrial Imron. As Aero said, often the color chips away leaving the primer, easy to fix. I am careful with installation, you cant help normal wear and tear but you don't got to beat the snot out of it putting it together. I always run a brite over after blast, it smooths it a lot, you can feel the difference and it knocks sand off. You can routinely get nearly auto grade finishes with a little practice and some acceptable place to paint.

[kevbooth]

I don't know how "engineered" the deal is, but...... As was stated before it is a motor mount for a converted automotive engine. 350 LT1 with bored and stroked to a 383 with a lot of perfomance mods. Makes around 450hp and 500 ft/lbs on and engine dyno. They gear it down with a 2.31 to 1 geared reduction unit to swing a 3 blade 12" wide kevlar prop.

I am basically reverse engineering the stand from what was previously in service. Just using better materials and triangulating some, while trying to reduce weight, where ever I can. I'm sealing all the tubes with welds any attachment holes will be sealed by welding "sleeve" into the holes.

I have to run coach a baseball game right now, but I'll come back later and give you guys a brief bio, maybe help clear up some of the "back woods" worries . I have a few more questions also.

Later,
Kev

[zmotorsports]

Kev, I have powder coated many parts that are in the .058" and .065" wall thickness for snowmobiles and ATVs and have not had any problems with any distortion or problems of any kind. Same with chrome plating for that matter. I have heard of some problems with hydrogen embrittlement when chrome plating but after discussing with my plater he reassured me that it is not as much an issue as it used to be. I have been using 4130 extensively for about 7 years now. Mike.

[Aerometalworker]

I have heard of some problems with hydrogen embrittlement when chrome plating but after discussing with my plater he reassured me that it is not as much an issue as it used to be. Mike.

Im sorry but that is a blanket false statement by the plater. And a very dangerous one at that. Sounds like the words from someone who has overstepped their knowledge and capability. My guess is the plater doesnt know the mechanics behind HE.

Always bake 4130 (and others) after plating....always, if you rely on the part to never fail.

If you dont believe me, believe the ASME handbooks.

-Aaron